Submission #706741

#	Time	Username	Problem	Language	Result	Execution time	Memory
706741		Yell0	Combo (IOI18_combo)	C++17	100 / 100	28 ms	528 KiB

combo

#include <bits/stdc++.h>
#include "combo.h"

using namespace std;

string guess_sequence(int N) {
  vector<char> ch={'A','B','X','Y'};
  if(press("AB")) {
    if(press("B")) swap(ch[0],ch[1]);
  } else {
    if(press("X")) swap(ch[0],ch[2]);
    else swap(ch[0],ch[3]);
  }
  string ans="";
  ans.push_back(ch[0]);
  for(int i=1;i<N-1;++i) {
    int r=press(ans+ch[1]+ans+ch[2]+ch[1]+ans+ch[2]+ch[2]+ans+ch[2]+ch[3]);
    if(r==i) ans.push_back(ch[3]);
    else if(r==i+1) ans.push_back(ch[1]);
    else ans.push_back(ch[2]);
  }
  if(ans.size()<N) {
    if(press(ans+ch[1])==N) ans.push_back(ch[1]);
    else {
      if(press(ans+ch[2])==N) ans.push_back(ch[2]);
      else ans.push_back(ch[3]);
    }
  }
  return ans;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:22:16: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   22 |   if(ans.size()<N) {
      |      ~~~~~~~~~~^~

• Subtask 1: 5 / 5
• Subtask 2: 95 / 95